Track press



July 30, 1963 J. H. PAHL 3,099,130

TRACK PRESS Filed March 22, 1960 4 Sheets-Sheet 1 INVENTOR. JkMe-s 19. PAl/L JrraR/ve'rs FIEZLL July 30, 1963 .1. H. PAHL 3,099,130

' TRACK PRESS Filed March 22, 1960 4 Sheets-Sheet 2 INVENTOR. JAMES 6 Par/4 Irma/vars July 30, 1963 J. H. PAHL TRACK PRESS Filed March 22, 1960 4 Sheets-Sheet 3 INVENTOR. J4Ma=s M P462 Guiana-4 July 30, 1963 J. H. PAHL 3,099,130

TRACK PRESS Filed March 22, 1960 4 Sheets-Sheet 4 INVENTORQ Inna-s P0194 3,899,130 TRACK PRESS James H. Pahi, Excelsior, Minn, assignor to Rodgers Hydraulic incorporated, Minneapolis, Minn, a corporation of Minnesota Filed Mar. 22, 1960, Ser. No. 16,744? 6 illaims. (Cl. 59-7) This invention relates generally to improvements in machines commonly known as track presses, the purpose of which is to assemble and disassemble the tracks of crawler or track-laying tractors.

Machines for this purpose are known in the art, for example being shown in the copending application of Vernon K. Quarve and John L. Rodgers, Jr., Serial No. 716,711, filed February 21, 1958, for Track Press, now US. Patent No. 3,075,346, issued Ian. 29, 1963. The use and operation of crawler-type tractors causes quite rapid wear on their tracks or treads, particularly since these machines often operate in sandy ground and are thus subject to rapid abrasion of their interfitting parts. As a result servicing of the tracks to maintain them in repair is a continuing problem, requiring that the tracks be taken from the machine, disassembled in part or in toto as circumstances may dictate and the replacement and rearrangment or resetting of worn parts may require, then reassembled and replaced upon the machine. Not only are the tracks very heavy and unwieldy but the servicing operation must be carried out both as rapidly and as inexpensively as possible in order to reduce the cost of the operation as such, but also to reduce to the absolute minimum the down time of the tractor while track repairs are being effected.

The kind of track here under consideration is, in efiect, an endless chain made up of a series of heavy, pivotally connected link sections having side links which overlap each other at their ends and are cross connected by interfitting pins and bushings forming cross members not only serving as pivot connections between the track sections but also as means for establishing drive engagement between the tracks and their drive and supporting sprockets and imparting propulsion movement to the tracks. Secured to each such track section is a ground or support surface engaging shoe in the form of a rectilinear heavy metal plate held to the respective side links by suitable cap screws (or bolts) with the adjacent edges or lips of adjacent shoes normally overlapping in planes extending crosswise of the track as a whole to present a substantially uninterrupted surface to the ground While still permitting proper relative flexing movements of the sections as the track passes around its said sprockets. These shoes which are sometimes also referred to as grousers are held to the side links of the track sections, as stated, by the cap screws or equivalent fasteners, and a complete disassembly or breakdown of the track to separate all of its component parts for servicing and replacement requires removal of these screws to free the shoes, after which the aforesaid cross memhere are pressed from the side links. In the latter process the pins and bushings are separated and it is this general operation that is carried out by the track press. In assembling the track these operational steps are, of course, reversed in their order but in most track servicing it will be found that the track need not be completely taken to pieces, and only as few parts as necessary are removed for replacement, while others are shifted in position or reset to present unworn portions to further wear, thus restoring the track to effective operating condition. Obviously the less the track need be torn apart the better since the saving of all possible time is an extremely important factor in the work.

To this end service operators are accustomed to per- 3,099,136 Patented July 36, 1963 form as much as possible of both the track section disassembly and reassembly with the track shoes in place, or with only the fastening screws therefor along one side of the track removed, thus effecting a substantial saving, and this is a well recognized procedure in the industry. It is the primary object of my invention to provide a track press which will facilitate servicing of track under these conditions, and particularly the reassembly of the track sections, by flexing or bending the track at the junction of the section being reassembled with the next and just completed, reassembled section, to the end that the operator may have a better View of his work and therefore may carry it out more accurately, with greater speed and with less strain and fatigue. A further object is to provide a track press having a work table or support for the track section being worked upon, which support is bent or sloped downwardly and forwardly toward the operator along a plane extending crosswise of the track and coinciding with the pivot axis and junction between the completed section and the section being assembled, so that the latter inclines downwardly and forwardly relative to the remainder of the track. This disposition of the track section on which the work is being performed locates it at such an angle that the operator, standing in a comfortably erect position in front of the machine, may look downwardly and see the section to the very best possible advantage, the longitudinal plane of the section lying substantially perpendicular to or at right angles to the operators normal line of sight. Thus the operator may look straight into the holes in the treads and side links of the track section and bring them into exact registry ready to receive the fastening cap screws, without requiring him to bend and lean over rearwardly above the tools, thus assuming not only a tiring position but one which often places the operators head in a dangerous position, or in dangerous proximity to the work. Equally important this downward-forward sloping of the track section being worked upon flexes it or bends it downward relative to the next section to the rear on the press, separating the normally overlapping lips between the adjacent track shoes sufiiciently to make it easier to see the work and for the operator to accurately adjust and press the track components into place. This is of value not only in setting up the press for a particular track but also is very helpful throughout the servicing operation. In addition many tractor tracks have projecting lugs on the edges of their shoes, which lugs project downwardly when the track is on the press and, striking the links, interfere with servicing operations on the track, with the shoes in place, or the edges of the shoes are notched and offer similar interference in the usual track press. The aforesaid bending or flexing of the track section on the forepart of the work table in effect swings these lugs or notched edges upwardly enough to either entirely clear or 'at least slide quite readily over the links and solves one of the great problems of work on tracks of these particular and often met types.

It is to be understood that while I herein describe and refer to my invention as primarily useful in servicing and repair operations on these tracks .it is also susceptible of use in the initial assembly or manufacture of the tracks, as will be readily appreciated.

These and other more detailed and specific objects will be disclosed in the course of the following specification, reference being had to the accompanying drawings, in which FIG. 1 is a top plan view of one version of a track press according to my invention, the same being of what is known as the double-ended variety in the sense that it embodies reciprocating tools at each end for operation upon both sides of a track. Only fragments being Worked upon as well as the particular operation being performed thereon. Such guiding and stroke limiting means is disclosed in detail in the copending application hereinabove identified and includes heavy rods 31 secured to front and rear ends of the ram heads 293tl, slidable endwise out through the frame ends 'l314, parallel with the axes of the cylinders 2526 and fitted with adjustable stop nuts 32 as seen in P16. 1. Tool bars 33 3-: are removably mounted, by cap screw and dowel mountings or equivalent as seen in FIG. 2, upon the ram heads 293tl and each carries suitable front and rear tools projecting inwardly in proper spacing to coincide with the axes of the pins and bushings of the track section in working position on the press, these tools being denoted collectively at 35 and shaped and sized according to the nature of their work and purpose.

The aforesaid conveyor mechanism 19 so far as material to an understanding of my present invention comprises an elongated, forwardly-rearwardly extending frame structure including sides 3537 between which, along the upper edges, are journaled a plurality of track supporting rollers 33. Said frame structure is movable upwardly and downwardly at its forward end, adjacent the frame it by means of a ram 39 pivoted at 4% to brackets 41 on the rear web 12 of the frame and having a reciprocating plunger 42 pivoted at 3 at the underside of a forward extension plate 4-4 of the conveyor mechanism. The rollers 38 are at least in part power rotated by any suitable means such as a drive motor 45 (FIG. 2) operating a series of sprocket chains 46 through a speed reducer 47 and which drive is shown for purposes of exemplification only. The track resting upon th rollers 33 may thus be moved toward the press or rearwardly away there-from, at the will of the operator, and to support the conveyor mechanism against forward or rearward displacement relative to the press frame side links 43 are pivoted at 4950 to the press and conveyor frame, while pivoted upright limit links or bars 51, parallel the ram 39, with slotted lost motion connections already seen in FIG. 2, permitting and prescribing the desired upward-downward adjustment of the front end of the conveyor previously described, with all said links contributing to provide support against lateral displacement. Said links 51 are pivoted at upper ends on the aforesaid plunger pivot 43 and the lost motion connections are on the axes of the ram pivot 40 as best seen in FIG. 3.

The retractable jaw 23 is remova-bly mounted atop the aforesaid carrier or yoke 24 by cap screws 52 (FIG. 2) or equivalent fasteners and the jaw is provided with spaced apart, upwardly opening front and rear notches or recesses 53-54. These notches receive the bushings E or E of the track and to fit tracks of different sizes the notches may be fitted with inserts (not shown) or the jaw may be removed and replaced with another having notches of different spacing or different size as may be required. The carrier 24 for the jaw '23 is slidable in the press frame between the front and rear webs 11 .2 thereof, with the front and rear, upper edges of the carrier fitted with sliding wear plates 55 engaging the inner surfaces of said webs, or similar wear plates 56 secured to these interior surfaces if so desired. Forward-rearward displacement of the jaw is thus prevented and the same is guided for generally upward and downward movement, but in addition the carrier 24 is fitted at its upper portion between spaced apart webs 57 (appearing in FIG. 1 to best advantage) serving as abutments in order to support the jaw against the thrust exerted by the tools as they are brought to the work. Furthermore the lower portion of the jaw carrier is fitted between cylindrical compression members 58 extending in laterally spaced relation through and between the frame webs 1l12 at the lower center part of the press frame. All of these components contribute to the proper guiding of the jaw and its carrier as the jaw is retracted, or extended to working position. In the latter position the jaw serves not only to position the track section but also functions as an abutment engaging the inner sides of the side links of the track sections as the tools force the bushings and pins from the links during disassembly or as the tools in turn replace the parts as disassembled, during the several steps in servicing a track. The jaw is retracted or extended by means of a ram, indicated generally at 59, the cylinder 60 of which is pivoted at 61 to a bolt 62 mounted through a tie bar 63 which joins the lower center edges of the frame webs 1112. This ram is located in a suitable recess '64 within the carrier 2dand the reciprocating plunger 65 of the ram is threaded or otherwise secured at 66 to the carrier, so that the selective admission of fluid to the opposite ends of the cylinder of; will raise and lower the jaw and its carrier as may be required.

The work table 2% is preferably made up of the spaced apart right and left hand bars or supports 21-22 which are located one at each side of the jaw 23 as has been prewiously described, although it will be understood that by properly shaping an opening in a larger, one piece work table support (not shown) to rovide clearance for the jaw, it may be possible in some instances to substitute such a single plate for the pair of bars as here shown. The separate parts, however, have the advantage of a flexibility of adjustment to suit them to use in connection with tracks of all sizes which may be encountered, and for purposes of making a part of such adjustments the rear tail portions 21 and 22 of the bars are widened and provided with angularly extending slots 57 through which are upwardly projected the studs 68 carried by the aforesaid extension or forwardly projecting shelf-like element 44 of the track conveyor mechanism 19. Nuts 69 are threaded on the studs 68 and when turned down thereon tightly upon the margins of the slots 67 will firmly anchor the bars -2122 to the conveyor extension 44 so that the bars may be moved upwardly and downwardly in accordance with corresponding movements or adjustments of the conveyor mechanism accomplished by the aforesaid ram 39. In addition the bars 2l22 maybe moved forwardly and rearwardly with respect to the conveyor and to the track press as a whole by loosening the nuts 69 and sliding the bars forwardly and rearwardly as the case may be, following which they are again secured in place by turning down the nuts upon the mounting studs. Due to the angularity of the slots 67, which converge in the forward direction (FIGS. 1 and 4), the forward movement of the bars 21 22 as just described will also cause the bars to move inwardly toward each other to decrease the spacing between them, whereas the rearward movement will increase such spacing. Thus it will be seen that the bars 21-22 have no less than three different adjustments, including their upward and downward movement with the conveyor, and the purpose is to maintain the angular junctions 70, between the rear or tail parts 21 -22 of the bars and their forward, downwardly bent and angled parts which lie alongside the jaw 23, in proper relationship with a line X, seen in FIG. 2, which corresponds with the pivot axis of the junction between the forwardmost track section A and the one immediately to the rear, which is designated here at A. This line X also coincides with the center of the rear notch 54 in the jaw 23 and it will be seen that it is the same distance as the corresponding line Z, which coincides with the forwardmost pivots of the front track section and the center of the front notch '53 in the jaw, from the center line Y of the rams which operate the tools as hereinbefore described. It should be noted that as the spacing between the plates 21 and 22 is narrowed the portion 7% will be moved forwardly in the desired manner to accommodate smaller track sections, Any further adjustrnent necessary to place or keep the junctions 70 in proper alignment may of course be made through operation of ram 39.

The importance of locating the points and bends 70 upon the work table supports as just described will be made clear in FIG. 3 wherein it will be noted that the a forwardm'ost track section A, resting of its own weight down upon the supports. 2122, will bend downwardly or be downwardly, forwardly flexed with respect to the next adjacent track section A. This angular, forwardly sloping position of the track section being worked upon (and of the supporting table surfaces, as well as the iaw and other components of the press) locates the critical parts in a plane which is substantially perpendicular to the line of sight of an operator standing comfortably erect at his station in front of the press. it is thus apparent that the angle above the work table supports between the supporting surfaces for the track section being worked upon and the adjacent track section is somewhat greater than 180. Thus the operator is able to see the work being performed without the necessity of assuming a tiring position, bent over the work, in addition to which the line of sight is such that the openings H and l for the cap screws G may be looked directly into and brought intoexact, proper registry, as is so vital in the reassembly operation upon the track. Also of importance is the fact that this flexing of the two track sections in question effectually spreads their normally over-lapping lips K apart so the operator is afiorded a view downwardly between the adjacent track shoes F on the track sections, which is a convenience of great assistance in properly aligning the parts, both in assembling and disassembling the track. It is necessary, in order to place the points 7% upon the work surface supports for the track at exactly the proper position to thus flex the forwardmost track section downwardly about its pivot connection with the next section, to adjust the bars 2122 forwardly and rearwardly to maintain these po nts 79 always at or very near the line designated X in FIG. 2 as Will be readily apparent.

When the machine is set up for racks of different pitch, in which the distance between the pivot axes for the sections varies, the jaw 23 must either be fitted with inserts or replaced with others in which the spacing between the notches 53-54 is correspondingly varied, requiring a corresponding adjustment of the work ltable supports for the track. Of course, a corresponding adjustment or replacement of the tool bars 3334 and the tools must be made, in addition to which a track having a pitch substantially less than that for example here indicated will also usually be narrower and of reduced dimensions throughout, so that the extension of the jaw 23 and the spacing between the bars 21-22 must be adjusted, and the bars must be raised and lowered along with the extension 44 of the conveyor to correspond. The angular relationship between the slots 67 is calculated to bring about the proper co-relation between the forward and rearward adjustments of the side bars 2122 and their spacing and it will be observed that since it is necessary for these bars only to clear the jaw 23, while providin. suificient supporting contact with the sides of the track sections, this spacing adjustment while important is not extremely critical.

In order to bring about the proper sloping or tilted positioning of the press parts as has just been described the frame it) and components carried thereby are disposed within the base frame 15 at an angle to the vertical as viewed from the end of the machine and clearly shown in FIGS. 2 and 3, and while I do not in any sense limit myself it may be noted that the angle of the various track supporting and working components of the press, with respect to the horizontal, is approximately twenty-three degrees. An angle of about this magnitude is found to work out best, from the standpoint of permitting the operator to obtain the best possible view of the work and also in flexing the track sections so that the lips K are spread apart sufiicicntly to enable a View to be had of the junction between the track sections immediately beneath, as has been previously described. Not only does such flexing of the track section A at the front of the string of track being worked upon produce the results enumerated 'hereinbefore, but it also solves one of the great problems of work upon those styles of track in which one of the lips K of the shoes F is either provided with lugs (not here shown) along its underside, or is slotted or notched to engage the next adjacent section of t e track, as indicated at M in PEG. 4. In either such case the assembly or disassembly of the track has been greatly hindered by the fact that track shoes thus constructed will not clear the side links when the track is laid out in a straight line or string, requiring considerable manipulation and the expenditure of a great deal more efio-rt and force than actually should be required in order to bring these parts into proper relative relationship. However, when the track section being worked upon is turned or flexed downwardly at an angle to the next, the lip K of the shoe on that section will clear the next track section without any difficulty whatsoever, and neither the lugs nor the notches in the lips offer any real problem in assembly or disassembly of the track under these circumstances.

it is understood that suitable modifications may be made in the structure as disclosed, provided such modifications come within the spirit and scope of the appended claims. Having now therefore fully illustrated and described my invention, what I claim to be new and desire to protect by Letters Patent is:

1. In a track press for servicing the sections of a tractor track which has a plurality of such sections pivotally connected at their junctions by cross members and with such sections fitted with removable rectilinear ground engaging shoes having normally overlapping adjacent edges; the combination comprising a frame, means on the frame for supporting adjacent track sections with the shoes on top while one such section is serviced, means on the frame spaced from said supporting means including fluid pressure actuated tools movable crosswise of said supporting means for operatively engaging the track section being serviced, the said supporting means including the combination of a jaw for engaging said cross members and a pair of angularly related supports adjacent said jaw, one such support for the track section being worked upon and the other such support for the next adjacent track section, the angle above said supporting means between said angularly related supports being greater than such that said track sections will be flexed and said overlapping adjacent edges of the shoes on these sections relatively moved to at least partially expose the junction between said sections to view from above, said jaw being positioned in lateral alignment with said one support.

2. A machine of the character described for assembling and disassembling the side links and cross pivot members of the sections of a tractor track the sections of which are provided with removable rectilinear ground engaging shoes held on the side links by 'cap screws and having normally overlapping adjacent edges; comprising a frame, means on the frame for supporting adjacent track sections with the shoes uppermost, means on the frame spaced from said supporting means including fluid pressure actuated tools movable on the frame crosswise with reference to said frame and said track and for operation upon the track sections one at a time, the said supporting means including two angularly related sup porting surfaces, one such surface supporting the track section being operated upon and the other such surface supporting the next adjacent track section to the rear, the angle above said support means between said two surfaces being somewhat greater than 180 and the forwardmost section slanting downwardly and forwardly from the horizontal to facilitate view of and proper alignment of the track shoe, its cap screws and the links therebelow.

3. A track press of the character described for work upon a track made up of pivotally connected sections, comprising a frame, a work table support for a track and having two angularly related parts, one of said parts having an upwardly facing surface extending in a plane, the other of said parts having an upwardly facing surface obtusely angled from said plane, said surfaces being positionable to engage at least two adjacent track sections and to flex them at their junctions to dispose one of such sections in a horizontal plane and the other of such sections in downwardly angled position with respect to the horizontal, an angularly positioned jaw movable on the frame and positioned adjacent said surfaces to supportably engage said angularly disposed track section, reciprocatable tools operatively associated with the frame for movement crosswise of said parts to work upon the track section engaged by said jaw and said jaw being positioned in alignment with said angularly related part which supports the other section in a downwardly angled position.

4. In a track press of the character described for operation by an operator from a station at one end thereof in working upon a tractor track which is made up of pivotally connected sections each having a shoe with an edge normally overlapping an edge of the next adjacent shoe and wherein the track is arranged in a string extending toward the operator station, a base frame, a press frame on said base frame, a jaw on said press frame for releasably engaging the section of the track nearest the operator station and supporting the same against lateral displacement, ram operated tools mounted for movement relative to said press frame laterally of said jaw toward one side at least of said track section engaged by the jaw for performing work on said section engaged by said jaw, a work table support for the track on said frame adjacent said jaw, said support projecting crosswise of the paths of the tools and having a forward part upwardly engaging the track section nearest the operator station and a rear part positioned in a substantially horizontal plane similarly engaging the next adjacent track section, and the forward part of the support engaging the track section nearest the operator station being slanted substantially downwardly and for- Wardly with respect to said rear part of the support whereby the two track sections so supported are relatively flexed and the section nearest the operator station is inclined angularly downward toward the operator station.

5. In a track press of the character described for operation by an operator from a station at the front end thereof in working upon a tractor track which is made up of pivotally connected sections each having a shoe with an edge normally overlapping an edge of the next adjacent shoe and wherein the track is arranged in a string extending toward the operator station, a base frame, a press frame on said base frame, a jaw on said press flame for releasably engaging the section of the track nearest the operator station and supporting the same against lateral displacement, ram operated tools mounted for movement relative to said press frame laterally of said jaw operative toward one side at least of said jaw for performing work on said section engaged by said jaw, a work table support for the track on said frame adjacent said jaw, said support projecting crosswise of the paths of the tools and having a forward part upwardly engaging the track section nearest the operator station and a rear part similarly engaging the next adjacent track section, the forward part of the support engaging the track section nearest the operator station being slanted substantially downwardly and forwardly with respect to said rear part of the support whereby the two track sections so supported are relatively flexed and the section nearest the operator station is inclined angularly downward toward the operator station, said forward and said rear part being positioned in different planes and meeting at an angle substantially exceeding 180, and means for moving the jaw upwardly and downwardly in a plane at right angles to that assumed by the said track section nearest the operator station.-

6 In a track press of the character described for operation by an operator from a station at the front thereof in working upon a tractor track which is made up of pivotally connected sections each having a shoe with an edge normally overlapping an edge of the next adjacent shoe and wherein the track is arranged in a string extending toward the operator'station, a base frame, a press frame on said base frame, a jaw on said press frame for releasably engaging the section of the track nearest the operator station and supporting the same against lateral displacement, ram operated tools on the press frame laterally of said jaw operative toward one side'at least of said jaw for performing work on said section engaged by said jaw, a work table support for the track on said frame adjacent said jaw, said support projecting crosswise of the paths of the tools and having a forward part upwardly engaging the track section nearest the operator station and a rear part similarly engaging the next adjacent track section, the forward part of the support engaging the track section nearest the operator station being slanted substantially downwardly and forwardly with respect to said rear part of the support whereby the two track sections so supported are relatively flexed and the section nearest the operator section is inclined angularly downward toward the operator station, said forward and said rear part being positioned in different planes and meeting at an angle substantially exceeding x1 said work table support comprising spaced apart bars located one at each side of the jaw, and means supporting the bars for adjustments forwardly and rearwardly and with respect to each other, said supporting means including means to vary their spacing.

References Cited in the file or" this patent UNITED STATES PATENTS 2,268,225 Rodgers Dec. 30', 1941 2,379,001 Hage June 26, 1945 2,895,289 Wognumet et al July 21, 1959 3,028,723 Kaplan et a1 Apr. 10, 1962 3,028,724 Kaplan et al Apr. 10, 1962 

1. IN A TRACK PRESS FOR SERVICING THE SECTIONS OF A TRACTOR TRACK WHICH HAS A PLURALITY OF SUCH SECTIONS PIVOTALLY CONNECTED AT THEIR JUNCTIONS BY CROSS MEMBERS AND WITH SUCH SECTIONS FITTED WITH REMOVABLE RECTILINEAR GROUND ENGAGING SHOES HAVING NORMALLY OVERLAPPING ADJACENT EDGES; THE COMBINATION COMPRISING A FRAME, MEANS ON THE FRAME FOR SUPPORTING ADJACENT TRACK SECTIONS WITH THE SHOES ON TOP WHILE ONE SUCH SECTIONS IS SERVICED, MEANS ON THE FRAME SPACED FROM SAID SUPPORTING MEANS INCLUDING FLUID PRESSURE ACTUATED TOOLS MOVABLE CROSSWISE OF SAID SUPPORTING MEANS FOR OPERATIVELY ENGAGING THE TRACK SECTION BEING SERVICED, THE SAID SUPPORTING MEANS INCLUDING THE COMBINATION OF JAW FOR ENGAGING SAID CROSS MEMBERS AND A PAIR OF ANGULARLY RELATED SUPPORTS ADJACENT SAID JAW, ONE SUCH SUPPORT FOR THE TRACK SECTION BEING WORKED UPON AND THE OTHER SUCH SUPPORT FOR THE NEXT ADJACENT TRACK SECTION, THE ANGLE ABOVE SAID SUPPORTING MEANS BETWEEN SAID ANGULARLY RELATED SUPPORTS BEING GREATER THAN 180* SUCH THAT SAID TRACK SECTIONS WILL BE FIXED AND SAID OVERLAPPING ADJACENT EDGES OF THE SHOES ON THESE SECTIONS RELATIVELY MOVED TO AT LEAST PARTIALLY EXPOSED THE JUNCTION BETWEEN SAID SECTIONS TO VIEW FROM ABOVE, SAID JAW BEING POSITIONED IN LATERAL ALIGNMENT WITH SAID ONE SUPPORT. 